The beta 195.39 beta Nvidia driver more or less fixes the SLI problem, but instability is still there regardless. I alt-tab all the time, come back and my pc slowly consumes more and more ram to the point where the machine cannot even shut down. Nvidia really needs to release a stable driver for Windows 7. I believe that Nvidia was responsible for 40% of all Vista crashes when it first came out, so I am going to assume their driver team probably lost some key engineers.
The only thing nVidia really have going is hardware based PhysX support (they deliberately disabled hardware support for other graphics vendors, so no more using an ATi card as the primary 3D renderer with an nVidia part for PhysX).
And really, once the OpenCL version of Havok is available, I'm betting PhysX support falls by the wayside since OpenCL is supported by all major gaming graphics vendors (ATi, nVidia, and Intel).
The irony is that ATi used to be known for buggy drivers and since Vista (now on Win 7 Ultimate 64-bit), it's been just the opposite with nVidia drivers being far less stable and easy to work with.
[Edited by jack_deth, 10/31/2009 6:02:13 PM]